i don't know your subject but if I ~ U³ then so it is , if W is ch-wdt and L is 'ch-Lgh then U²/R =P but P·U = IU² ((i'm)cheking units/dimensions)
then if unit for k' has /V² in it ?? if it's µ.eff "...The quantity μeff is effectively dimensionless ..." then λ has /V² . . . the google helps us out